LCD Monitor problem

My dad recently got himself an 18" Proview PL688B, and it's worked very well. However, it has developed a problem that causes the screen to go black after about 3 seconds of being on. No sound, no light change, no flicker, - it just goes black suddenly until you turn it on, then off- then it goes black after another 3 seconds. I formatted his hard drive once before, and that seemed to help, but it's happened again. He's running an old TNT2, and I was wondering if having such an old video card might be causing the problem. Any ideas?

Process of elminination, put a different monitor on his machine and see what it does. I'd guess its the monitor though gone bad though.

I have switched monitors, and others work fine. Tech support said that it was probably something with my settings (the display settings where you select monitor type, the video card drivers, etc.), and when I formatted it worked again. My dad tried to install Quicktime and his monitor was suddenly assed, so it's most likely a touchy monitor, I think. Also, it's running in 1024x768 (not it's native res of 1280x1024). Might that be the problem?

Just uninstalled quicktime by switching out monitors, and it's working again. Could this be a 3-way clash between monitor/vid card/visual programs? (Last time I think it was something to do with multiple video card drivers)

Strange... quicktime shouldnt/wouldnt have anything to do with his display adapter or monitor... But its windows and if its working now then HEY!

Seriously. I dunno what's up with it. It looks great and all, but that's really the only problem it has. Good times.